Mary Stuart chose crimson underclothes to symbolize martyrdom at her execution

Evidence

The black velvet gown fell below her knees revealing underbodice and petticoat of crimson silk, and she stepped forward suddenly, shockingly, in the colour of martyrdom, blood red from top to toe, against the sombre background. — Garrett Mattingly, The Defeat of the Spanish Armada, 38

Categorization

• FICTION: The deliberate color choice stagecraft of the execution clothing is perfect sensory scene material for a narrative.
• SEED: Color-as-message in royal executions: Mary’s crimson undergarments as planned martyrdom iconography.
• corroborated: 2 independent passages support this claim — Garrett Mattingly, The Defeat of the Spanish Armada, 38
• XREF: connects to: Mary Stuart staged her execution in martyr’s red as a final defiant statement — Garrett Mattingly, The Defeat of the Spanish Armada, 38; Mary Stuart dominated her own trial scene through practiced theatrical presence — Garrett Mattingly, The Defeat of the Spanish Armada, 31